1. Field of the Invention
The present invention relates to a breath-based diagnostic device. In particular, the present invention relates to a breath-based diagnostic device including a array of multiple sensors. The present invention also relates to a breath-based diagnostic method.
2. Description of the Related Art
Many disorders are accompanied with elevated volatile organic chemical (VOC) levels in the patent""s breath due to abnormal metabolism. Diagnosis of such disorders can therefore be achieved by breath test. However, disorder-related VOC presents in very low concentration in the breath and therefore requires high sensitivity to detect. Disorder-related VOC often contains more than one chemical and results from breath test are often complex, requiring extensive analysis. Gas chromatographyxe2x80x94mass spectrometer analysis has been used in breath test diagnosis. For example, U.S. Pat. Nos. 5,996,586 and 6,180,414 disclose such method for diagnosis. However, gas chromatographyxe2x80x94mass spectrometer analysis requires a large amount of breath to be concentrated into a suitable sample. Also, the data collected from a gas chromatographyxe2x80x94mass spectrometer needs to be compared with a spectrum to obtain a useful result.
The object of the present invention is to solve the previously mentioned problems when using the gas chromatographyxe2x80x94mass spectrometer method, and therefore provide a device enabling diagnosis of disorder or physiological state directly from breath. The present invention also provides a diagnostic method using the device. The diagnostic device of the present invention is non-invasive and quick. The operation of the diagnostic device is easy and thus no complex training is required. Moreover, with the diagnostic device of the present invention, sample concentration and heating process are avoided and multiple chemicals can be analyzed at the same time.
The diagnostic device of the present invention utilizes a multi-sensor array to detect specific volatile organic chemicals (VOC) in the breath. The multi-sensor array carries a substance that is reactive to the VOC as a sensory receptor. The data collected is compared with a database for a variety of disorders to diagnose disorders or physiological state. The database is built up by statistically analyzed data for the disorders.
Accordingly, the diagnostic device of the present invention comprises a multi-sensor array, a database storage device and a microprocessor. The multi-sensor array comprises a plurality of sensory devices, each reacting with specific VOC in breath to generate a signal. Each of the sensory devices reacts with the VOC directly or through a sensory receptor coating on the sensory device. The database contains information for a variety of disorders in the form of a pattern and/or digital record. The microprocessor receives the signal generated by the multi-sensor array and compares the signal with information stored in the database to give a result.
Another aspect of the present invention is a diagnostic method for disorder diagnosis. The method comprises the following steps. Breath to be tested is collected and allowed to react with a multi-sensor array. A signal is generated from the reaction and sent to a microprocessor. The signal is then compared with information in a database to determine the physiological state of the person. The multi-sensor array comprises a plurality of sensory devices each reacting with specific VOC in breath to generate a signal. Each of the sensory devices reacts with the VOC directly or through a receptor coating on the sensory device. The database contains information for a variety of disorders in the form of a pattern and/or digital record. The microprocessor receives the signal generated by the multi-sensor array and compares the signal with information stored in the database to give a diagnosis result.
According to the features of the present invention, the sensory device of the multi-array is a quartz crystal sensory device, a metal oxide semiconductor (MOS) sensory device, a surface acoustic wave (SAW) device, an electrode device, or a fiber optic device. MOS sensory device and electrode device are capable of reacting with specific VOC themselves. On the other hand, quartz crystal sensory device, SAW, and fiber optic devices need to be coated with an additional sensory receptor that reacts with specific VOC in the breath. Quartz crystal sensory device can be, for example, a piezoelectric quartz crystal sensory device.
According to another feature of the present invention, the sensory receptor is a conductive macromolecule, organic compound, organelle, peptide, protein, antibody, nucleic acid, metal oxide or metal.
According to another feature of the present invention, the signal generated from the multi-array is a pattern signal or a digital signal. The pattern, for example, can be a fingerprint, block chart, wave chart, or radio diagram.
According to another feature of the present invention, the diagnostic device is suitable for the diagnosis of disorders such as uremia, cirrhosis, hyper methionine disorder, ketoacidosis, diabetes, periodontosis, gingivitis, lung cancer, pulmonary abscess, schizophrenia, and intestinal obstruction.
According to another feature of the present invention, the diagnostic device of the present invention is suitable for the diagnosis of disorders relating to abnormal metabolism or microorganism infectious disease.
According to another aspect of the present invention, the method for disorder diagnosis of the present invention is suitable for the diagnosis of disorders such as uremia, cirrhosis, hyper methionine disorder, ketoacidosis, diabetes, periodontosis, gingivitis, lung cancer, pulmonary abscess, schizophrenia, and intestinal obstruction.
According to another aspect of the present invention, the method for disorder diagnosis of the present invention is suitable for the diagnosis of disorders relating to abnormal metabolism or microorganism-based infectious disease.